– The flood that has a 1-percent chance of being equaled or exceeded in any given year. (Source: FEMA)
Base Flood Elevation (BFE) – The elevation of a flood having a 1-percent chance of being equaled or exceeded in any given year. (Source: FEMA)
Closure Devices – Any movable and essentially watertight barriers, used during flood periods to close openings in levee systems, securing but not increasing the levee systems’ design level of protection. (Source: FEMA)
Deficiency – An identified element or item which does not meet current levee criteria or is different than what was originally constructed.
Emergency Action Plan (EAP) – The purpose of an EAP is to facilitate and organize appropriate agencies and personnel in times of flooding or other emergencies. (Source: OSHA)
Emergency Preparedness Plan (EPP) – Emergency preparedness plans are intended to provide a clear and effective structure with which to manage an emergency. Preparedness activities may include development of emergency action plans, communication strategies, exercises, and training emergency response teams; as well as management and stockpile of disaster supplies and equipment. (Source: FEMA)
Flash Flood – A rapid flooding of low-lying areas, which is caused by intense rainfall from a thunderstorm or several thunderstorms. Flash floods can also occur from the collapse of a man-made structure such as a levee or dam. (Source: NWS)
Flood – A general and temporary condition of partial or complete inundation of normally dry land areas from (1) the overflow of inland or tidal waters or (2) the unusual and rapid accumulation or runoff of surface waters from any source (Source: FEMA)
Flood Advisory – A Flood Advisory is issued when a specific weather event that is forecast to occur may become a nuisance. A Flood Advisory is issued when flooding is not expected to be bad enough to issue a warning. However, it may cause significant inconvenience, and if caution is not exercised, it could lead to situations that may threaten life and/or property. (Source: NWS)
Flood Insurance Rate Map (FIRM) – The insurance and floodplain management map produced by FEMA that identifies, based on detailed or approximate analyses, the areas subject to flooding during a 1-percent-annual-chance flood event in a community. Flood insurance risk zones, which are used to compute actuarial flood insurance rates, also are shown. In areas studied by detailed analyses, the FIRM shows BFEs and/or base flood depths to reflect the elevations of the 1-percent-annual-chance flood. For many communities, when detailed analyses are performed, the FIRM also may show areas inundated by 0.2-percent-annual-chance flood and regulatory floodway areas. (Source: FEMA)
Floodwall – Concrete wall constructed adjacent to shorelines for the purpose of reducing flooding of property on the landward side of the wall. Floodwalls are normally constructed in lieu of or to supplement levees where the land required for levee construction is too expensive or not available. (Source: FEMA)
Flood Warning – A Flood Warning is issued when the hazardous weather event is imminent or already happening. A Flood Warning is issued when flooding is imminent or occurring. (Source: NWS)
Flood Watch – A Flood Watch is issued when conditions are favorable for a specific hazardous weather event to occur. A Flood Watch is issued when conditions are favorable for flooding. It does not mean flooding will occur, but it is possible. (Source: NWS)
Hazard – An event or physical condition that has the potential to cause fatalities, injuries, property damage, infrastructure damage, agricultural loss, damage to the environment, interruption of business, and other types of loss or harm. (Source: FEMA)
Interior Drainage – Natural or modified outflow of streams within an area landward of the levee for the conveyance of runoff. (Source: FEMA)
Interior Drainage Systems – Systems associated with levee systems that usually include storage areas, gravity outlets, pumping stations, or a combination thereof. (Source: FEMA)
Levee – A man-made structure, usually an earthen embankment, designed and constructed in accordance with sound engineering practices to contain, control, or divert the flow of water so as to provide protection from temporary flooding. (Source: FEMA)
Levee Breach – A rupture, break, or gap in a levee system that causes flooding in the adjacent area and whose cause has not been determined. (Source: FEMA)
Levee Failure Breach – A rupture, break, or gap in a levee system that causes flooding in the adjacent area and for which a cause of failure is both known and occurred without overtopping. An investigation is usually required to determine the cause. (Source: FEMA)
Levee Overtopping – Floodwater levels that exceed the crest elevation of a levee system and flow into areas landward of the levee landward of the levee system. (Source: FEMA)
Levee Overtopping Breach – A rupture, break, or gap in a levee system that causes flooding in the adjacent area and whose cause is known to be a result of overtopping. (Source: FEMA)
Levee System – A flood hazard-reduction system that consists of a levee, or levees, and associated structures, such as closure and drainage devices, which are constructed and operated in accordance with sound engineering practices. (Source: FEMA)
LPSNRD – Lower Platte South Natural Resources District; the local sponsor of the Salt Creek Levee System
National Levee Database (NLD) – The focal point for comprehensive information about our nation’s levees. Authorized by Congress in 2007, the database contains information to facilitate and link activities, such as flood risk communication, levee system evaluation for the National Flood Insurance Program (NFIP), levee system inspections, flood plain management, and risk assessments. The NLD continues to be a dynamic database with ongoing efforts to add levee data from federal agencies, states, and Tribes. (Source: FEMA)
NWS – National Weather Service
Piping – The phenomenon where seeping water progressively erodes and washes away soil particles, leaving large voids in the soil. Removal of soil through sand boils by piping or internal erosion damages levees, their foundations, or both, which may result in settlement and has the potential to cause catastrophic failures of levees. (Source: FEMA)
Public Law 84-99 Rehabilitation Program (PL 84-99) – A United States Army Corps of Engineers (USACE) program which provides flood damage rehabilitation assistance to levee sponsors who are in good standing within the program.
Residual Risk – The risk that remains after all structural and non-structural measures are employed to reduce flood risk.
Risk – The United States Army Corps of Engineers (USACE) defines risk as the probability of a hazard occurring (e.g., rare flooding, levee/dam failure) multiplied by the consequences (e.g., number of structures flooded) that would be expected if the hazard were to occur.
Salt Creek and Tributaries Flood Control Project – The name of the United States Army Corps of Engineers (USACE) project responsible for the construction of the Salt Creek Levee System, as well as channel and dam projects.
Sand Boils – The volcano-like cones of sand that that are formed on the landward side of a levee system when the upward pressure of water flowing through soil pores under a levee (underseepage) exceeds the downward pressure from the weight of the soil above it. (Source: FEMA)
Seepage – See under-seepage.
System Wide Improvement Framework (SWIF) – A plan to address maintenance needs and deficiencies identified which is coordinated with the United States Army Corps of Engineers. (Source: USACE)
Under-seepage – The upward pressure on the land landward of a levee system that is exerted by groundwater, under pressure from the flooding source, when the elevation of the floodwaters is higher than the elevation of the land. (Source: FEMA)
USACE – United States Army Corps of Engineers
USGS – United States Geological Survey
Weather Radio – A radio receiver that is capable of receiving weather and/or warning information from applicable government agencies.